Detection of H. pylori by culture from gastric biopsy and sensitivity testing

Description of test

• Culture from gastric biopsy on selective medium
• Determination of antibiotic resistance profile for positive cultures by the Etest method according to EUCAST recommendations.

Purpose of the test

• Determination of the presence of H. pylori and sensitivity to antibiotics.
• Criteria for performing this test in the context of reference activities.
• Therapeutic failure of eradication treatment

Instructions for samples

Biopsy during endoscopy: optimally two biopsies (one antral and one fundus).

Instructions for transport

• H. pylori is very sensitive to dehydration and exposure to oxygen (air)
• If delivered directly to the laboratory and placed in culture within 4 h → biopsy in a sterile container with 1-2 ml of sterile physiological water at 4°C.
• If the period is between 4 and 24 h → place biopsy in a suitable transport medium (e.g.: Portagerm pylori, bioMérieux) at 4°C.
• For a period longer than 24 h → freeze biopsy at-80°C in suitable transport medium (see above, and remove any compresses) and delivery on dry ice (or liquid nitrogen).

Unacceptable requests

• Sample not identified
• Mandatory fields on the application form incomplete
• Obvious storage and/or transport conditions not applied
• A biopsy sent to the laboratory and sampling date evidences long storage in inappropriate conditions
• A biopsy kept in fixation medium (formaldehyde, Bouin)
• Stomach lavage

Turn around time (and frequency of analysis)

• Cultures and PCRs for H. pylori are performed every day from Monday to Friday
• Interpretation culture and sensitivity tests are performed 3 times a week (Monday — Wednesday - Friday)
• Results are sent after 3 working days for negative samples and within 3 weeks for positive samples.

Reporting of test results

A protocol is sent to the requesting laboratory by post.